He says the speed at which new developments are emerging in the biological sciences is increasingly bringing about conflicts with the Vatican. In particular Webb sees this in relation to reproductive technologies -- such as in vitro fertilization, and egg and sperm donation -- all of which the Church says are improper methods of procreation.
"The church is taking its viewpoint from 2,000-year-old teachings and trying to apply them to a modern world, which is delivering all sorts of moral dilemmas," he said to CNN.
Webb doubts there will be any significant change in the Vatican's fundamental attitude to contraception under Francis and believes this will remain a sticking point between the biological sciences and the church.
"Catholics believe that anything that threatens the sanctity of life -- including contraception -- is wrong. That is a barrier and it will always be a barrier."
There have been no signals yet as to whether Pope Francis will bring about a softening of the Vatican's stance on issues such as condom-use as means to prevent suffering and early death.
Werner Arber is optimistic that the Vatican will eventually catch up with the scientific evidence: "I have hope but - as with Galileo -- it will take a long time."